This invention relates to an apparatus for mounting on the feeder housing of a combine harvester to drive reverse rotation of the combine harvester feeder housing to release blockages.
It is a well known problem on the feeder housing of a combine harvester that excessive feed of crop material can occur and cause a blockage. Many devices have been proposed and are available for reversing the drive to automatically release the blockage by propelling the excess material back down the feeder housing to the header.
One proposed device comprises an electric motor of the type used as a starter motor in an automobile. When the motor is actuated it moves into engagement with the drive chain to the feed elements of the feeder housing and acts to reverse the drive chain.
It is of course necessary to maintain the reverse drive system so that it does not interfere with the normal forward drive system of the combine. In the electric motor arrangement, this is effected by retracting the motor from the drive system.
The electric motor is however disadvantageous in that it requires a significant level of power to be drawn from the battery of the combine harvester. The battery power is not intended to provide this amount of power and accordingly the reversing system generates an excessive load on the battery and alternator system.
An alternative arrangement has been proposed utilizing a hydraulic motor which is connected to the drive chain through a torque converter arrangement permanently attached to the chain. The hydraulic motor therefore does not interfere with the normal forward rotation of the chain, but when the chain is stopped, the hydraulic motor can be brought into action and drive the chain in the reverse direction through the torque converter arrangement. This construction is however disadvantageous in view of the fact that it is relatively complex and therefore relatively expensive and is difficult to repair on breakdown.
It is one object of the present invention, therefore, to provide an improved hydraulic drive system for reversing the drive of the feeder housing of a combine harvester.